Last month, we announced support for tagging Amazon DynamoDB tables when you create them in all standard AWS Regions. Today, we extend tagging support to the AWS GovCloud (US) Regions. Tags are labels you can attach to AWS resources to make them easier to manage, search, and filter.

from Recent Announcements https://aws.amazon.com/about-aws/whats-new/2019/06/amazon-dynamodb-now-supports-tagging-tables-when-you-create-them-in-the-aws-govcloud-us-regions/